> Il giorno 16 giu 2017, alle ore 18:15, Christoph Hellwig <hch@xxxxxx> ha scritto:
>
> icq_to_bic is a container_of operation, so we need to check for NULL
> before it. Also move the check outside the spinlock while we're at
> it.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
> block/bfq-iosched.c | 15 +++++----------
> 1 file changed, 5 insertions(+), 10 deletions(-)
>
> diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c
> index 4f69e39c2f89..f037b005faa1 100644
> --- a/block/bfq-iosched.c
> +++ b/block/bfq-iosched.c
> @@ -4398,16 +4398,17 @@ static int bfq_get_rq_private(struct request_queue *q, struct request *rq,
> struct bio *bio)
> {
> struct bfq_data *bfqd = q->elevator->elevator_data;
> - struct bfq_io_cq *bic = icq_to_bic(rq->elv.icq);
> + struct bfq_io_cq *bic;
> const int is_sync = rq_is_sync(rq);
> struct bfq_queue *bfqq;
> bool new_queue = false;
> bool split = false;
>
> - spin_lock_irq(&bfqd->lock);
Thanks for taking a step I feared here (basically for cowardice) ...
> + if (!rq->elv.icq)
> + return 1;
> + bic = icq_to_bic(rq->elv.icq);
>
> - if (!bic)
> - goto queue_fail;
> + spin_lock_irq(&bfqd->lock);
>
> bfq_check_ioprio_change(bic, bio);
>
> @@ -4465,13 +4466,7 @@ static int bfq_get_rq_private(struct request_queue *q, struct request *rq,
> bfq_handle_burst(bfqd, bfqq);
>
> spin_unlock_irq(&bfqd->lock);
> -
> return 0;
> -
> -queue_fail:
> - spin_unlock_irq(&bfqd->lock);
> -
> - return 1;
> }
>
> static void bfq_idle_slice_timer_body(struct bfq_queue *bfqq)
> --
> 2.11.0
>
Acked-by: Paolo Valente <paolo.valente@xxxxxxxxxx>
